rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=28197, q=1419 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 2793 (4294972307-4294969514), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 2794 jiffies! g28197 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:26504 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6701
 schedule+0xbd/0x170 kernel/sched/core.c:6775
 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x30d/0x1590 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7956 Comm: syz.1.518 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:178 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:241 [inline]
RIP: 0010:__sanitizer_cov_trace_switch+0x7f/0xe0 kernel/kcov.c:346
Code: c9 eb 08 49 ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 65 44 8b 1d 2b 22 7c 7e 41 81 e3 00 01 ff 00 74 13 41 81 fb 00 01 00 00 75 d9 <41> 83 b8 24 16 00 00 00 74 cf 45 8b 98 00 16 00 00 41 83 fb 03 75
RSP: 0018:ffffc900000068b0 EFLAGS: 00000246
RAX: 0000000000000008 RBX: 0000000000000000 RCX: 0000000000000003
RDX: ffffffff813bbb18 RSI: ffffffff8cfa0900 RDI: 0000000000000005
RBP: ffffc90000006a58 R08: ffff8880287e3c00 R09: 0000000000000004
R10: 0000000000000006 R11: 0000000000000100 R12: ffffffff8f0f810e
R13: ffffc90000006a08 R14: 0000000000000005 R15: dffffc0000000000
FS:  00007f6f1bc8a6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb82fc4feb8 CR3: 0000000026917000 CR4: 00000000003506f0
DR0: 0000000000000008 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 unwind_next_frame+0x748/0x2990 arch/x86/kernel/unwind_orc.c:515
 __unwind_start+0x5bb/0x730 arch/x86/kernel/unwind_orc.c:760
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xf8/0x190 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522
 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
 kasan_slab_free include/linux/kasan.h:164 [inline]
 slab_free_hook mm/slub.c:1811 [inline]
 slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837
 slab_free mm/slub.c:3830 [inline]
 kmem_cache_free+0xf8/0x290 mm/slub.c:3852
 skb_release_all net/core/skbuff.c:1052 [inline]
 __kfree_skb net/core/skbuff.c:1068 [inline]
 kfree_skb_reason+0xd7/0x170 net/core/skbuff.c:1104
 kfree_skb include/linux/skbuff.h:1264 [inline]
 ip6_mc_input+0xa17/0xc10 net/ipv6/ip6_input.c:589
 ip_sabotage_in+0x1e2/0x270 net/bridge/br_netfilter_hooks.c:1005
 nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline]
 nf_hook_slow+0xbd/0x200 net/netfilter/core.c:626
 nf_hook include/linux/netfilter.h:259 [inline]
 NF_HOOK+0x21d/0x3b0 include/linux/netfilter.h:302
 __netif_receive_skb_one_core net/core/dev.c:5670 [inline]
 __netif_receive_skb+0xcc/0x290 net/core/dev.c:5784
 netif_receive_skb_internal net/core/dev.c:5870 [inline]
 netif_receive_skb+0x1bc/0x720 net/core/dev.c:5929
 NF_HOOK+0x9e/0x3a0 include/linux/netfilter.h:304
 br_handle_frame_finish+0xf51/0x15c0 net/bridge/br_input.c:221
 br_nf_hook_thresh+0x3cd/0x4a0 net/bridge/br_netfilter_hooks.c:1188
 br_nf_pre_routing_finish_ipv6+0x9e5/0xd20 net/bridge/br_netfilter_ipv6.c:-1
 NF_HOOK include/linux/netfilter.h:304 [inline]
 br_nf_pre_routing_ipv6+0x34d/0x6a0 net/bridge/br_netfilter_ipv6.c:184
 nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:277 [inline]
 br_handle_frame+0x1240/0x14d0 net/bridge/br_input.c:424
 __netif_receive_skb_core+0xf94/0x3ac0 net/core/dev.c:5564
 __netif_receive_skb_one_core net/core/dev.c:5668 [inline]
 __netif_receive_skb+0x74/0x290 net/core/dev.c:5784
 process_backlog+0x380/0x710 net/core/dev.c:6112
 __napi_poll+0xbb/0x460 net/core/dev.c:6674
 napi_poll net/core/dev.c:6741 [inline]
 net_rx_action+0x65f/0xcc0 net/core/dev.c:6877
 handle_softirqs+0x27d/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:preempt_schedule_irq+0xba/0x150 kernel/sched/core.c:7011
Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 6f bf 01 00 00 00 e8 61 fa c1 f6 e8 ac 03 f3 f6 fb bf 01 00 00 00 <e8> 31 b4 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f
RSP: 0018:ffffc900034df780 EFLAGS: 00000282
RAX: f84f378f9ae71600 RBX: ffff8880287e3c00 RCX: f84f378f9ae71600
RDX: dffffc0000000000 RSI: ffffffff8acacce0 RDI: 0000000000000001
RBP: ffffc900034df820 R08: ffffffff911f052f R09: 1ffffffff223e0a5
R10: dffffc0000000000 R11: fffffbfff223e0a6 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff9200069bef0
 irqentry_exit+0x67/0x70 kernel/entry/common.c:441
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:put_cpu_partial+0x1b0/0x250 mm/slub.c:2742
Code: 3b 44 24 18 0f 85 b4 00 00 00 48 83 c4 20 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 1c df b2 08 f7 c5 00 02 00 00 74 c0 fb 4d 85 e4 <75> bf eb c8 e8 37 54 51 02 85 c0 0f 84 e9 fe ff ff 83 3d 18 cb ac
RSP: 0018:ffffc900034df8e8 EFLAGS: 00000286
RAX: f84f378f9ae71600 RBX: ffff88814224d640 RCX: f84f378f9ae71600
RDX: dffffc0000000000 RSI: ffffffff8acacce0 RDI: ffffffff8b1d4020
RBP: 0000000000000286 R08: ffffffff911f052f R09: 1ffffffff223e0a5
R10: dffffc0000000000 R11: fffffbfff223e0a6 R12: ffffea0000af7800
R13: 0000000000000000 R14: ffff8880287e3c00 R15: ffff8880b8e443d0
 __slab_free+0x319/0x400 mm/slub.c:3700
 qlink_free mm/kasan/quarantine.c:166 [inline]
 qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185
 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6a/0x4d0 mm/slab.h:770
 slab_alloc_node mm/slub.c:3495 [inline]
 __kmem_cache_alloc_node+0x194/0x250 mm/slub.c:3534
 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098
 kmalloc include/linux/slab.h:600 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 percpu_ref_init+0xc3/0x340 lib/percpu-refcount.c:76
 css_create kernel/cgroup/cgroup.c:5569 [inline]
 cgroup_apply_control_enable+0x428/0xb00 kernel/cgroup/cgroup.c:3219
 cgroup_mkdir+0xc83/0xe70 kernel/cgroup/cgroup.c:5779
 kernfs_iop_mkdir+0x241/0x3e0 fs/kernfs/dir.c:1246
 vfs_mkdir+0x2a5/0x470 fs/namei.c:4168
 do_mkdirat+0x1dc/0x450 fs/namei.c:4191
 __do_sys_mkdirat fs/namei.c:4206 [inline]
 __se_sys_mkdirat fs/namei.c:4204 [inline]
 __x64_sys_mkdirat+0x89/0xa0 fs/namei.c:4204
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6f1ad9e199
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6f1bc8a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f6f1b026090 RCX: 00007f6f1ad9e199
RDX: 00000000000001ff RSI: 0000200000000000 RDI: ffffffffffffff9c
RBP: 00007f6f1ae358e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6f1b026128 R14: 00007f6f1b026090 R15: 00007ffc94cb2368
 </TASK>
net_ratelimit: 2080 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:1e:3c:28:a2:36:d9, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:1e:3c:28:a2:36:d9, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:1e:3c:28:a2:36:d9, vlan:0)
net_ratelimit: 3325 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:1e:3c:28:a2:36:d9, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:1e:3c:28:a2:36:d9, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)